A recent study published in Biology Letters may have solved the mystery of the infamous "Chicago Rat Hole" on the sidewalk.
Scientists analyzed the measurements of the imprint and believe it resembles a squirrel, rather than a rat, due to its stocky and semi-aquatic characteristics, as well as webbed feet.
The Chicago Rat Hole was previously located near Roscoe Street and Damen Avenue before its removal.
The impression resembles a squirrel: stocky and semi-aquatic, with webbed feet.
Author's summary: Scientists solve Chicago Rat Hole mystery.